Electric Uterine Massager (EUM) device versus manual uterine massage for postpartum bleeding and pain after vaginal delivery: study protocol for a randomized controlled trial

Postpartum hemorrhage and postpartum pain are common concerns after vaginal delivery. Manual uterine massage is routinely used in many settings; however, it is operator-dependent and may be uncomfortable for mothers, with inconsistent evidence regarding its effectiveness. Technology-assisted approaches to postpartum uterine stimulation have been explored but remain limited. This trial aims to evaluate whether a novel non-invasive electric uterine massager (EUM) can reduce early postpartum blood loss and pain compared with routine manual uterine massage. This is a two-phase study. Phase I involved the design, development, and preliminary safety testing of a handheld, non-invasive EUM device with adjustable vibration and a detachable medical-grade silicone head. Phase II is an assessor-blinded, parallel-group, randomized controlled superiority trial to be conducted in hospitals affiliated with Mashhad University of Medical Sciences, Iran. Eligible participants are low-risk women with singleton term pregnancy (37–42 weeks) undergoing uncomplicated vaginal delivery. Participants will be randomized (1:1) using simple randomization with sealed opaque envelopes to receive either intermittent uterine massage using the EUM device or routine manual uterine massage. In both groups, uterine stimulation will be applied intermittently every 15 minutes for 30–60 seconds during the first 2 hours postpartum.The co-primary outcomes are (1) postpartum bleeding volume at 1 and 2 hours measured using gravimetric methods (pad/drape weighing) and (2) postpartum pain intensity assessed using a visual analogue scale (VAS) during the first 2 hours after delivery. Secondary outcomes include adverse events and need for additional interventions (if applicable). Analyses will follow the intention-to-treat principle, using appropriate parametric or non-parametric tests; multiplicity for co-primary outcomes will be addressed using Holm–Bonferroni adjustment or a pre-specified joint success criterion. This trial will provide evidence on the effectiveness and tolerability of a standardized, technology-assisted uterine stimulation method in the immediate postpartum period. If beneficial, the EUM device may offer a feasible alternative to manual uterine massage by reducing operator dependency and improving maternal comfort. Iranian Registry of Clinical Trials (IRCT) IRCT202207120554338N3 Registered on 2026.05.30.